1. Technical Field
The present invention relates to a digital mixer capable of easily changing a parameter used in performing signal processing on an input signal.
2. Background Art
In the related art, there is known a digital mixer which adjusts levels or frequency characteristics of audio signals output from a plurality of microphones or electrical and electronic instruments, mixes the audio signals, and transmits the mixed audio signals to a power amplifier, and which is used in a concert hall or the like. Such a digital mixer is disclosed, for example, in Japanese patent application laid-open No. 2006-262079. An operator who operates a digital mixer adjusts the sound volume or tone of each audio signal of musical instrument sound or song to an optimum state, which is considered to express the performance most suitably, by operating various kinds of panel controls in the digital mixer. The digital mixer includes a plurality of input channels as an input signal process, a bus which mixes signals output from the input channels, and a plurality of output channels which is an output signal system that outputs mixed signals. Each input channel controls the frequency characteristics, mixing levels, and the like of input signals and outputs the signals to each mixing bus, and each mixing bus mixes the input signals and outputs the mixed signal to the corresponding output channel. An output from the output channel is amplified and is then emitted from a speaker or the like.
In a known digital mixer, various parameters for signal processing are prepared in the input channel and output channel. Each of the parameters may be changed by a user, and a selection channel operating portion for loading and changing a parameter in a selected channel is prepared. In order to change a parameter of a specific channel, a user has changed the parameter by selecting the specific channel and operating a control, such as a knob control, corresponding to the parameter to be changed in the selection channel operating portion. In this case, channel strips for a plurality of channels are prepared on a panel of the digital mixer. A channel assigned to a channel strip whose SEL button is operated last among SEL buttons provided in each channel strip becomes a ‘selected channel’. In addition, an encoder operated to rotate is provided in each channel strip. Allocation of a parameter changed by the encoder is performed by a touch operation on a control symbol (graphic control) displayed on an indicator using a touch panel, and a parameter corresponding to a control symbol operated by a touch operation is assigned to an encoder.
However, touch action to the touch panel needs to be performed while viewing control symbols displayed on the indicator, and the control symbols displayed on the indicator are not physically separated controls. Accordingly, there is a problem that a wrong parameter is assigned to the encoder when a neighboring control symbol is inadvertently touched by mistake.